Head gate for a cattle containment chute

ABSTRACT

An animal head gate includes head gate doors each having a squeeze bar to trap the neck mounted between upper and lower rails. Adjustment of the spacing between the bars uses an eccentric crank operated by lever which cooperates with two manual latches on a rail at maximum and minimum spacing. A neck sweep bar is mounted on one gate and movable from a retracted position to a position forward of the squeeze bar across the head gate so as to engage the neck of the animal in front of the squeeze bar and to turn the neck and head. The head gate is held closed by front and rear abutment members each of which is formed as a roller which rotates to reduce friction under load. Each gate includes an upstanding torsion bar which twists when forces are applied to the squeeze bars from impact with the animal.

This invention relates to a head gate for a cattle containment chutewhere cattle are confined to pass in a row through a chute with a headgate at the end and to a head gate arrangement which can make it easierfor the handler to control movement of the animal in the chute and tobetter contain the animal when engaged by the head gate.

BACKGROUND OF THE INVENTION

Squeeze chutes are well known and conventionally include a generallychannel shaped frame structure having a head end for receiving a head ofan animal to be confined, two sides each for extending along arespective side of the animal to be confined, a tail end remote from thehead end. A head gate assembly at the head end is operable to move froma release position to a closed position in which the neck of the animalis grasped for confinement of the animal. In some cases, a squeeze sidepanel is arranged along one side both and is operable in a pivotingaction to squeeze the animal from one side onto the other side panel sothat the body of the animal is also confined. A tail gate section isoften provided at the rear end to close behind the animal as it entersthe squeeze chute.

The head gate typically comprises a pair of upstanding squeeze bars witha spacing between them sufficient to receive the neck of the animalwithout damage but insufficient for the head to be pulled out of thebars and insufficient for the animal to move forward. Each of theupstanding squeeze bars forms part of a head gate door which pivotsabout a vertical axis parallel to the upstanding squeeze bar and spacedoutwardly of the bar. In the closed holding position the axis and theupstanding squeeze bars lie in a common plane transverse to the chutewith the upstanding squeeze bars at their point of closest approach. Ina set portion the bar pivots so that it moves along the chute toward theincoming animal with the frame inclined out of the common plane thusincreasing the space between the bars.

Thus to catch the cattle by the head, it is common to have a head gatethat locks by itself as the cattle try to walk through it. When set inthe set catch position, the bars are turned toward the approachingcattle. The approaching animal will see an opening sufficient for itshead and try to walk through. The head will fit through the opening, butas the animal tries to walk forward its shoulders hit the bars and thebars move forward with the shoulders until the bars hit a latch at a topof the head gate locking them in the catch or closed position in whichthe upstanding squeeze bars lie in the common plane. Normally head gatedoors have a handle projecting out of the frame of one of the bars toone side of the chute which allows a worker standing to that side topush the handle to pivot the frame about its vertical axis that helpspivot the head gate to be closed.

Head gates have been manufactured in this construction for many yearsand many manufacturers have arrangements which operate effectively inthis manner. It will be appreciated that the animals concerned are verylarge and strong with great ability to do damage to themselves and theworker. It is thus highly desirable that even highly recalcitrantanimals are trapped in the head gate as quickly and simply as possiblewith little possibility to back up before being trapped.

SUMMARY OF THE INVENTION

The arrangement described herein provide a number of improvements overconvention head gates.

A first improvement relates to a quick width adjustment where theupstanding squeeze bars can be adjusted relative to the respective headgate door so as to adjust the point of closest approach to accommodateanimals of different sizes. this is particularly important where theanimals approaching the head gate are of different sizes to that theoperator can quickly change the spacing as the animal is in it approachto properly trap smaller animals while avoiding potential injury to theanimal if the spacing is too small.

In accordance with this important feature, there is provided an animalconfinement apparatus comprising:

a generally channel shaped frame structure having a head end forreceiving a head of an animal to be confined, two sides each forextending along a respective side of the animal to be confined, a tailend remote from the head end;

a head gate assembly at the head end operable to move from an openposition to a closed position in which the neck of the animal is graspedfor confinement thereof; the head gate assembly comprising:

-   -   a support frame mounted on the frame structure at the head end;    -   a pair of head gate doors;    -   each head gate door having a respective upstanding squeeze bar        for cooperating with a respective upstanding squeeze bar of the        other of the doors to trap the neck of the animal therebetween;    -   each head gate door being mounted on a hinge support member        carried on the support frame for pivotal movement of the door        and its respective upstanding squeeze bar about a respective        pivot axis generally parallel to the respective upstanding        squeeze bar and spaced outwardly toward a respective side of the        support frame;    -   each head gate door comprising an upper rail and a lower rail        each connected to the hinge support member for pivotal movement        about the pivot axis;    -   the head gate doors being movable from a closed position in        which the respective upstanding squeeze bars lie in a common        plane including the pivot axes to a rearward open position in        which the respective upstanding squeeze bars are positioned on a        side of the common plane facing the tail end to allow the head        of the animal to enter and to a forward open position in which        the respective upstanding squeeze bars are positioned on a side        of the common plane opposite the tail end to allow the animal to        depart;    -   the upstanding squeeze bar of each head gate door being mounted        at an upper end on the respective upper rail for adjustment        movement toward and away from the pivot axis;    -   each head gate door having an adjustment device for causing said        adjustment movement comprising:    -   an eccentric crank mounted on the upper rail rotatable about a        crank axis transverse to the upper rail;    -   an upper link connecting the eccentric crank to the upstanding        squeeze bar where rotation of the eccentric crank about the        crank axis causes the upstanding squeeze bar to move toward and        away from the pivot axis in said adjustment movement;    -   and a manually operable lever for driving rotation of the        eccentric crank around the crank axis.

The eccentric crank operated by the lever therefore can rapidly andimmediately adjust the bar of each door between two positions, thusproviding three separate spacings defined by the bars being both in theclosest positions, one being moved outwardly and both being in thewidest positions. This quick adjustment can allow the skilled operatorto select from the three positions that which is most suitable for theapproaching animal so that the animal is properly confined without riskof injury to an animal which is too small or too large for the selectedspacing.

According to a second definition of this arrangement there is providedan animal confinement apparatus comprising:

a generally channel shaped frame structure having a head end forreceiving a head of an animal to be confined, two sides each forextending along a respective side of the animal to be confined, a tailend remote from the head end;

a head gate assembly at the head end operable to move from an openposition to a closed position in which the neck of the animal is graspedfor confinement thereof; the head gate assembly comprising:

-   -   a support frame mounted on the frame structure at the head end;    -   a pair of head gate doors;    -   each head gate door having a respective upstanding squeeze bar        for cooperating with a respective upstanding squeeze bar of the        other of the doors to trap the neck of the animal therebetween;    -   each head gate door being mounted on a hinge support member        carried on the support frame for pivotal movement of the door        and its respective upstanding squeeze bar about a respective        pivot axis generally parallel to the respective upstanding        squeeze bar and spaced outwardly toward a respective side of the        support frame;    -   each head gate door comprising an upper rail and a lower rail        each connected to the hinge support member for pivotal movement        about the pivot axis;    -   the head gate doors being movable from a closed position in        which the respective upstanding squeeze bars lie in a common        plane including the pivot axes to a rearward open position in        which the respective upstanding squeeze bars are positioned on a        side of the common plane facing the tail end to allow the head        of the animal to enter and to a forward open position in which        the respective upstanding squeeze bars are positioned on a side        of the common plane opposite the tail end to allow the animal to        depart;    -   the upstanding squeeze bar of each head gate door being mounted        at an upper end on the respective upper rail for adjustment        movement toward and away from the pivot axis;    -   each head gate door having an adjustment device for causing said        adjustment movement comprising:        -   a manually operable lever movable between first and second            positions;        -   a latch arrangement which latches said lever in said first            and second positions;        -   and a link connection connecting the lever to the upstanding            squeeze bar where movement of the lever causes the            upstanding squeeze bar to move toward and away from the            pivot axis in said adjustment movement.

Preferably there is provided therefore a latch arrangement for locatingthe lever in at least two adjustment positions of maximum and minimumspacing from the pivot axis.

Preferably the upstanding squeeze bar of each head gate door is mountedat a lower end on the respective lower rail for adjustment movementtoward and away from the pivot axis; wherein each head gate door has alower link mounted at the lower rail where causes the lower end of theupstanding squeeze bar to move toward and away from the pivot axis insaid adjustment movement and wherein the manually operable leverincludes a coupling for driving rotation simultaneously of the upper andlower links.

The eccentric crank arrangement is one preferred way in which a rotationof the lever causes a simple quick linear adjustment of the position ofthe squeeze bar. However other arrangements can be used.

Using this arrangement, adjustment can take place in some embodiments inas little as 2 seconds allowing the worker to adjust for the actualapproaching animal in the stream of animals rather than to set up inadvance which is necessary in prior art devices where adjustment cantake up to several minutes.

Preferably the upstanding squeeze bar of each head gate door is mountedat a lower end on the respective lower rail for adjustment movementtoward and away from the pivot axis; wherein each head gate door has alower link mounted at the lower rail where rotation of the eccentriccrank about the crank axis causes the lower end of the upstandingsqueeze bar to move toward and away from the pivot axis in saidadjustment movement and wherein the manually operable lever includes acoupling for driving rotation simultaneously of the upper and lowerlinks. In this arrangement, preferably the coupling comprises a bargenerally parallel to the upstanding squeeze bar.

Preferably the crank axis is upstanding so as to be generally parallelto the upstanding squeeze bar.

Preferably the manually operable lever includes an upstanding arm orhandle allowing it to be easily grasped and which cooperates with athumb operated latch on a rail of the respective head gate door parallelto and above the upper rail. In this way the operator can each up to thehandle and quickly release it from its latch using thumb pressure andcrank it around to a second position lying along the upper rail where itis engaged by a second latch. This avoids the use of conventionaltelescopic tubes and latching pins which are very slow and cumbersome.

Thus preferably the manually operable lever cooperates with first andsecond latches on a rail of the respective head gate door parallel tothe upper rail and the manually operable lever is movable between firstand second positions extending longitudinal of the upper rail andcooperates in said first and second positions with first and secondlatches on a rail of the respective head gate door parallel to the upperrail.

A second improvement relates to a neck sweep bar which is mounted on oneof the head gate doors to move across in front of the associated squeezebar so as sweep the head and front part of the neck of the animal acrossto one side to better expose one side of the neck and head for treatmentfor example by injection or for tagging.

In accordance with this important feature, there is provided an animalconfinement apparatus comprising:

a generally channel shaped frame structure having a head end forreceiving a head of an animal to be confined, two sides each forextending along a respective side of the animal to be confined, a tailend remote from the head end;

a head gate assembly at the head end operable to move from an openposition to a closed position in which the neck of the animal is graspedfor confinement thereof; the head gate assembly comprising:

-   -   a support frame mounted on the frame structure at the head end;    -   a pair of head gate doors;    -   each head gate door having a respective upstanding squeeze bar        for cooperating with a respective upstanding squeeze bar of the        other of the doors to trap the neck of the animal therebetween;    -   each head gate door being mounted on a hinge support member        carried on the support frame for pivotal movement of the door        and its respective upstanding squeeze bar about a respective        pivot axis generally parallel to the respective upstanding        squeeze bar and spaced outwardly toward a respective side of the        support frame;    -   each head gate door comprising an upper rail and a lower rail        each connected to the hinge support member for pivotal movement        about the pivot axis;    -   the head gate doors being movable from a closed position in        which the respective upstanding squeeze bars lie in a common        plane including the pivot axes to a first open position in which        the respective upstanding squeeze bars are positioned on a side        of the common plane facing the tail end to allow the head of the        animal to enter and to a second open position in which the        respective upstanding squeeze bars are positioned on a side of        the common plane opposite the tail end to allow the animal to        depart;

and an upstanding neck sweep bar mounted on a respective one of the headgate doors at a position in front of the head gate door and movablerelative thereto from a retracted position to one side of the respectiveupstanding squeeze bar of the respective head gate door to an operatingposition forward of the respective upstanding squeeze bar of the headgate and spaced across the head gate to a greater distance than therespective upstanding squeeze bar of the respective head gate door so asto engage the neck of the animal in front of the respective upstandingsqueeze bar of the respective head gate door and to turn the neck andhead to a side opposite the respective head gate door;

a linkage mounting the neck sweep bar on the frame structure for pivotalmovement between the retracted and extended positions;

and a manually operable lever for causing said pivotal movement of thelinkage and thus the neck sweep bar.

Preferably the linkage includes a latch to hold the neck sweep bar at aplurality of positions relative to the respective head gate door. Thelatch can comprise a simple sliding friction lock which is infinitelyadjustable to hold the neck sweep bar at the positions and can include amanually release to allow the neck sweep bar return to its retractedposition when the animal is ready for release. It will be appreciatedthat the close confinement of the animal and particularly the head andneck acts to reduce stress leading to uncontained thrashing movementswhich can interfere with the treatment and particularly case brokeninjection needles which become embedded in the meat after slaughter.

Preferably the neck sweep bar is mounted for pivotal movement about thehinge support member of the respective head gate door and preferablythere is provided a pivot link connected to the respective head gatedoor to guide movement of the neck sweep bar in an arc from a positionto one side of the squeeze bar around in a sweeping action to a positionaligned with and in front of the squeeze bar and beyond the squeeze barto push the head and neck to one side as required.

Preferably the neck sweep bar cooperates with a neck holding bar on theother one of the head gate doors where the neck holding bar is locatedin front of the upstanding squeeze bar of the other of the head gatedoors. Preferably the neck holding bar pivots relative to the upstandingsqueeze bar of the other one of the head gate doors to a deployedposition from a retracted position closer to the pivot axis. This avoidsa situation where the space between the squeeze bars appears to theanimal to be partly closed thus restricting the tendency to pass throughbetween the squeeze bars. Thus the neck holding bar is retracted in theset position of the doors so that it is hidden from the animal until itis deployed as the animal moves the doors to the closed position.

That is, preferably the neck holding bar is automatically moved to thedeployed position as the other one of the head gate doors is moved tothe closed position. Preferably the neck holding bar is fixed in thedeployed position and the neck sweep bar is movable to selectedadjustable positions adjacent the neck holding bar depending on the sizeof the neck of the animal. In this way the holding bar locates one sideof the neck and the sweep bar pushes the other side of the neck acrossthe space between the squeeze bars to the required inclined position.

Preferably the neck sweep bar is not straight but includes a recess ataround head height on the animal to restrict up and down movement whenconfined.

A further improvement relates to an improved latching arrangement wherethe head gate doors can more easily be released from the latchedposition, bearing in mind that the large animals involved can beapplying heavy pressure forwardly or rearwardly to the gates when therelease is required.

In accordance with this important feature, there is provided an animalconfinement apparatus comprising:

a generally channel shaped frame structure having a head end forreceiving a head of an animal to be confined, two sides each forextending along a respective side of the animal to be confined, a tailend remote from the head end;

a head gate assembly at the head end operable to move from an openposition to a closed position in which the neck of the animal is graspedfor confinement thereof; the head gate assembly comprising:

-   -   a support frame mounted on the frame structure at the head end;    -   a pair of head gate doors;    -   each head gate door having a respective upstanding squeeze bar        for cooperating with a respective upstanding squeeze bar of the        other of the doors to trap the neck of the animal therebetween;    -   each head gate door being mounted on a hinge support member        carried on the support frame for pivotal movement of the door        and its respective upstanding squeeze bar about a respective        pivot axis generally parallel to the respective upstanding        squeeze bar and spaced outwardly toward a respective side of the        support frame;    -   each head gate door comprising an upper rail and a lower rail        each connected to the hinge support member for pivotal movement        about the pivot axis;    -   the head gate doors being movable from a closed position in        which the respective upstanding squeeze bars lie in a common        plane including the pivot axes to a rearward open position in        which the respective upstanding squeeze bars are positioned on a        side of the common plane facing the tail end to allow the head        of the animal to enter and to a forward open position in which        the respective upstanding squeeze bars are positioned on a side        of the common plane opposite the tail end to allow the animal to        depart;

each head gate door including an engagement portion cooperating with alatching device for latching the head gate door in the closed position;

the latching device having a front abutment member for engaging aforward surface of the engagement portion to hold the engagement portionand thus the head gate door against movement to the forward openposition and a rear abutment member for engaging a rearward surface ofthe engagement portion to hold the engagement portion and thus the headgate door against movement to the rearward open position;

the front abutment member being movable in a direction generally alongthe common plane to release the forward surface to allow movement of thehead gate door to the forward open position;

the rear abutment member being movable in a direction generally alongthe common plane to release the rearward surface to allow movement ofthe head gate door to the rearward open position;

the front abutment member comprising a roller which rotators to rollover the forward surface;

the rear abutment member comprising a roller which rotators to roll overthe rearward surface.

Preferably the front abutment member includes two separate rollers eachfor engaging respective one of the head gate doors the rear abutmentmember includes two separate rollers each for engaging respective one ofthe head gate doors.

Preferably the front abutment member and the rear abutment member areindependently operable.

Preferably the front abutment member and the rear abutment member areoperable manually.

Preferably the front abutment member and the rear abutment member arelocated at a top of head gate doors.

Preferably the engagement portion comprises an upstanding post.

Preferably the front abutment member and the rear abutment member arespring mounted so as to move to allow entry of the engagement portiontherebetween.

Preferably the front abutment member is connected to a front lift rollerfor lifting the front abutment member when the head gate door movestoward the closed position and the rear abutment member is connected toa rear lift roller for lifting the rear abutment member when the headgate door moves toward the closed position.

Preferably there is provided a front manually operable member arrangedto move the front abutment member to a raised position to release thehead gate door and a rear manually operable member arranged to move therear abutment member to a raised position to release the head gate door,the front and rear members being connected to a tilt mechanism to allowto move one or other to the raised position.

Preferably each of the head gate doors includes a hand grasp handleadjacent the front abutment member projecting forward from the head gatedoor.

Preferably each of the head gate doors includes a projecting bar abovethe respective upstanding squeeze bars extending across from the headgate door toward the other head gate door so as to prevent a part of theanimal being pinched at the latching device.

A further improvement relates to the provision in the structure of eachhead gate door of a torsion bar which allows the head gate door to twistunder impact loads to reduce forces on the animal which could causeinjury.

In accordance with this important feature, there is provided an animalconfinement apparatus comprising:

a generally channel shaped frame structure having a head end forreceiving a head of an animal to be confined, two sides each forextending along a respective side of the animal to be confined, a tailend remote from the head end;

a head gate assembly at the head end operable to move from an openposition to a closed position in which the neck of the animal is graspedfor confinement thereof; the head gate assembly comprising:

-   -   a support frame mounted on the frame structure at the head end;    -   a pair of head gate doors;    -   each head gate door having a respective upstanding squeeze bar        for cooperating with a respective upstanding squeeze bar of the        other of the doors to trap the neck of the animal therebetween;    -   each head gate door being mounted on a hinge support member        carried on the support frame for pivotal movement of the door        and its respective upstanding squeeze bar about a respective        pivot axis generally parallel to the respective upstanding        squeeze bar and spaced outwardly toward a respective side of the        support frame;    -   each head gate door comprising an upper rail and a lower rail        each connected to the hinge support member for pivotal movement        about the pivot axis;    -   the head gate doors being movable from a closed position in        which the respective upstanding squeeze bars lie in a common        plane including the pivot axes to a rearward open position in        which the respective upstanding squeeze bars are positioned on a        side of the common plane facing the tail end to allow the head        of the animal to enter and to a forward open position in which        the respective upstanding squeeze bars are positioned on a side        of the common plane opposite the tail end to allow the animal to        depart;

the upstanding squeeze bar of each head gate door being looselyconnected at an upper end thereof to the upper rail for movementrelative to the upper rail;

the upstanding squeeze bar of each head gate door being looselyconnected at a lower end thereof to the lower rail for movement relativeto the lower rail;

a latching arrangement at a top of the head gate doors which locks thehead gate doors in the closed position while bottom ends of head gatedoors at the lower rails are free to pivot about the pivot axis;

and an upstanding torsion bar rigidly connected at an upper end to theupper rail and rigidly connected at a lower end to the lower rail;

the upstanding torsion bar being located between the upstanding squeezebar and the hinge support member;

the upstanding torsion bar being arranged so as to twist when forces areapplied to the upstanding squeeze bars from impact with the animal wherethe forces are communicated to the latching arrangement at the upperends while the bottom ends pivot about the pivot axis.

Preferably the upstanding squeeze bar of each head gate door is looselyconnected at the upper end thereof to the upper rail for slidingadjustment movement relative to the upper rail and the upstandingsqueeze bar of each head gate door is loosely connected at a lower endthereof to the lower rail for sliding adjustment movement relative tothe lower rail.

Preferably the torsion bar is welded to the upper and lower rails.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention will now be described in conjunctionwith the accompanying drawings in which:

FIG. 1 is an isometric view of a cattle confinement chute including ahead gate according to the present invention.

FIG. 2 is a front elevational view of the head gate of FIG. 1 in theclosed position.

FIG. 3 is a front elevational view of the head gate of FIG. 1 in theclosed position showing adjustment of the squeeze bar of one head gatedoor to a wider position.

FIG. 4 is an isometric view of the head gate of FIG. 1 .

FIG. 5 is a cross sectional view of the head gate along the lines 5-5 ofFIG. 2 .

FIG. 6 is an isometric view of the neck sweep system of the head gate ofFIG. 1 .

FIG. 7 is an isometric view of an upper part of the head gates showingthe latching arrangement.

FIG. 8 is a cross sectional view of the latching arrangement of FIG. 7 .

FIG. 9 is a cross sectional view of the width adjustment system of FIGS.2 and 3 .

In the drawings like characters of reference indicate correspondingparts in the different figures.

DETAILED DESCRIPTION

A squeeze chute generally indicated at 10 is formed by a frame structure11 forming a front panel 20, a rear panel 13, a first side 14 and asecond side 15. Each of the panels is formed by vertical posts so thatthe front panel includes posts 16 and 17 and the rear panel includesposts 18 and 19. The front and rear panels are connected by horizontalrails 12 and 21 at the top part of the frame forming a rigid channelshaped frame structure into which an animal to be confined can enterfrom the rear panel to a position between the side panels and rearwardlyof the front panel.

The front panel includes a head gate assembly generally indicated at 22including a first head gate door 23 and a second door 24 each of whichis pivotally mounted for opening and closing movement around a verticalaxis at or adjacent the post 16, 17 from a closed or confinementposition shown in FIG. 1 to a receiving position in which the doors arepivoted to face inwardly and to the chute so that the animal pushes itshead between the doors as it tries to escape out of the front of thesqueeze chute with the animal automatically pushing the doors to theclosed confinement position as it engages the doors. The doors can thenbe pivoted to a release position facing outwardly of the front of thesqueeze chute in which the animal can escape when the confinement is nolonger required.

As shown the doors are mounted for pivotal movement around axes 16A, 17Aat or adjacent the vertical posts 16 and 17 on hinge collars 16B, 16Cand 17A, 17B. A diagonal lever 10A is provided which connects the doors23. 24 and ensures that the doors remain in synchronism so that if onedoor is pushed, both of the doors move into the required location. Eachof the doors can be manually operated by levers 25A and 25B attached tothe respective door which projects outwardly from the door toward theside of the squeeze chute. The levers can pivot downwardly as shown whennot used. A handle at the end of the lever can be grasped to lift thelever allowing the worker to pivot the gate and thus synchronously theother gate from one position to another.

The pair of head gate doors 23 and 24 are arranged with each door havinga vertical or upstanding squeeze bar 26, 27 for cooperating with thesqueeze bar of the other of the doors to trap the neck of the animaltherebetween. Each door is mounted on the hinge support member 16, 17carried on the support frame for pivotal movement of the door and itsvertical bar about a respective vertical pivot axis 16A, 17A generallyparallel to the first vertical post member and spaced outwardly toward arespective side of the support frame 11.

The doors are movable from the closed position shown in which thesqueeze bars lie in a common plane P (FIG. 5 ) including the pivot axes16A, 17A to an open position in which the vertical bars are positionedon a side of the common plane P facing the rear end of the chute and theincoming animals to allow the head of the animal to enter between thebars while they are spaced apart.

The head gate assembly 22 at the head end at the front end is thusoperable to move from an open position (not shown) to a closed positionin which the neck of the animal is grasped for confinement between thesqueeze bars 26, 27.

The head gate assembly comprises a support frame 28 mounted on the framestructure of the chute 10 at the head end or front end. The supportframe is defined by the posts 16 and 17 which are connected at the topby a cross rail 30 and at the bottom by a cross rail 29.

The pair of head gate doors 23, 24 each have the respective upstandingsqueeze bar 26, 27 for cooperating with a respective upstanding squeezebar of the other of the doors to trap the neck of the animaltherebetween. The bars are straight and parallel but other shapes arepossible to better hold the head of the animal.

Each head gate door is pivotally mounted on its respective hinge supportmember defined by its respective post 16, 17 carried on the supportframe 28 for pivotal movement of the door 23, 24 and its respectiveupstanding squeeze bar 26, 27 about its respective pivot axis 16A, 17Awhich is generally parallel to the respective upstanding squeeze bar andspaced outwardly toward a respective side of the support frame.

Each head gate door 23, 24 comprising an upper rail 31 welded to thecollar 16C, 17C and a lower rail 32 welded to the collar 16B, 17B eachmounted on the hinge support member 16, 17 for pivotal movement aboutthe pivot axis 16A, 17A. The collars 16B and 16C are separate and hencecan pivot independently around the respective post. The top rail 31 isconnected to the bottom rail by a torsion bar 34 welded to both rails sothat the structure defined by the top and bottom rails and the torsionbar lies in a common plane but can distort out of that plane undersufficient force.

The head gate doors are therefore movable from a closed position inwhich the respective upstanding squeeze bars lie in a common planeincluding the pivot axes to a rearward open position in which therespective upstanding squeeze bars are positioned on a side of thecommon plane facing the tail end to allow the head of the animal toenter and to a forward open position in which the respective upstandingsqueeze bars are positioned on a side of the common plane opposite thetail end to allow the animal to depart.

The upstanding squeeze bar 26, 27 of each head gate door is mounted atan upper end on the respective upper rail 31 for sliding adjustmentmovement toward and away from the pivot axis 16A, 17A. This mountingcomprises a channel 35 in which the top rail 31 sits so that the channelcan slide along the rail to change the distance of the squeeze bar fromthe pivot axis and thus from the squeeze bar of the other gate.Symmetrically the lower end of the squeeze bar is attached to the bottomrail 32 by an inverted channel 36 which sits on the bottom rail and canalso slide longitudinally of the bottom rail. As the connection betweenthe squeeze bar and the top and bottom rail is not rigid, the squeezebar does not contribute to the rigidity of the head gate door so thatthis can flex as stated above by twisting of the torsion bar 34.

Each head gate door includes an adjustment device 37 for causingadjustment movement of the respective squeeze bar along the top andbottom rails.

Turning to FIG. 3 , the adjustment device 37 comprises an eccentriccrank 38 mounted on the upper rail 31 for rotation in a bushing 39rotatable about an upstanding crank axis 39A transverse to the upperrail. The crank attaches to an upstanding connection rod 40 which isoffset from the crank axis so that rotation of the crank around thebushing axis causes the connecting rod to rotate around the axis of thecrank from the inward position shown on the left of FIG. 3 to theoutward position shown on the right of FIG. 3 . The lower end 40A of thecoupling rod 40 is mounted in a symmetrical crank 41 carried in abushing 42 attached to the bottom rail.

The coupling rod 40 is attached at the top and bottom to the squeeze barby a pair of connected flanges 43 so that the lateral movement of thecoupling bar is communicated to the squeeze bar 26 by the coupling barwith the squeeze bar held in lateral movement only along the rail by thechannel coupling 35, 36.

In this way the coupling defined by the coupling rod 40 and the flanges43 provides that rotation of the eccentric crank about the axis of itsbushing causes the upstanding squeeze bar 26 to move toward and awayfrom the pivot axis in the adjustment movement.

A manually operable lever 44 is provided for driving rotation of theeccentric crank around the crank axis. The lever 44 includes anupstanding handle 45 which can be readily grasped by the worker andmoved between two positions as shown.

A latch arrangement 46 is provided for locating the handle 45 of thelever 44 in two adjustment positions of maximum and minimum spacing fromthe pivot axis 16A.

Symmetrically the upstanding squeeze bar of each head gate door ismounted at a lower end on the respective lower rail for adjustmentmovement toward and away from the pivot axis; and each head gate doorhas a lower link mounted at the lower rail where rotation of theeccentric crank 38 about the crank axis 39 causes the lower end of theupstanding squeeze bar 26, 27 to move toward and away from the pivotaxis 16A, 17A in adjustment movement. The manually operable lever 44includes the coupling bar 40 for driving rotation simultaneously of theupper and lower links where the coupling bar extends generally parallelto the upstanding squeeze bar. The manually operable lever cooperateswith first and second latches 47, 48 mounted on a rail 49 of therespective head gate door parallel to the upper rail 31. Thus themanually operable lever 44 is movable between first and second positionsextending longitudinal of the upper rail 31 and cooperates in the firstand second positions with the first and second latches 47, 48 on therail 49 fixed to the respective head gate door parallel to the upperrail and movable with the door. The latches are pivotally mounted on therail so that the thumb of the worked can be applied to one end of thelatch thus releasing the other end from holding the upper end of thehandle 45 in the respective latched position. In this way the worked caninstantly switch the latch lever from one position to the other tochange the spacing between the squeeze bars for animals of differentsize.

Turning now to FIGS. 4, 5 and 6 there is shown an upstanding neck sweepbar 50 mounted on the head gate door 24 at a position in front of thehead gate door 24 and movable relative thereto from a retracted positionto one side of the upstanding squeeze bar 27 of the head gate door 24 toan operating position forward of the upstanding squeeze bar 27 of thehead gate 24. The neck sweep bar 50 extends generally parallel to thesqueeze bar 27 and has a height generally matching the bar 27. The bar50 is generally straight but can include a recessed notch 51 at theheight of the head of the animal be engaged.

The bar 50 in its operating position shown in FIGS. 4 and 6 is spacedacross the head gate to a greater distance than the squeeze bar 27 ofthe head gate door 24 so as to engage the neck of the animal in front ofthe squeeze bar 27 and to turn the neck and head to a side opposite thehead gate door 24 toward the head gate door 23.

The retracted position is shown in FIG. 5 where the bar 50 is retractedinwardly of the squeeze bar 27 so that it has no influence on the animalapproaching from the rear. When the animal is engaged between the bars26 and 27, the neck sweep bar can be deployed from the retractedposition in an arc A to the operating position.

A linkage 54 mounts the neck sweep bar on the frame structure forpivotal movement between the retracted and extended positions andincludes a lever 55 carried on cranks 57 and 58 which guide the motionand create the arc A between the retracted and deployed positions. Thecrank 57 is attached to a collar 56 mounted in the post 17 for rotationaround the axis 17A. The crank 58 is mounted on a collar 59 carried onthe torsion bar 34. The lever 55 is operable by a handle 60 so thatrotation of the handle in a clockwise direction causes movement in thedeployment direction.

The mounting linkage includes a latch to hold the neck sweep bar at aselected one of plurality of positions relative to the head gate doorwhere the latch comprises a rod 62 sliding through a hole in a plate 63acting as a friction lock to hold the neck sweep bar at the requiredposition and where the plate includes a manually operable release handle64 to allow the neck sweep bar return to the retracted position drivenby a spring 65.

In this way the neck sweep bar is mounted for pivotal movement about thehinge support member 17 of the head gate door 24. The rod 58 is carriedon a bracket 66 which allows the rod to follow the required path to actas a friction lock on the movement of the sweep bar 51.

The neck sweep bar 50 cooperates in holding the neck with a neck holdingbar 67 on the other head gate door 23. That is the neck holding bar 67of the gate 23 is deployed to a position in front of the squeeze bar 26of the gate 23 and then remains fixed as the operator actuates the necksweep bar 50 to a required position using the handle 60. The requiredposition will vary depending on the animal and the required treatmentusing the skill of the worker to properly locate the head and neck ofthe animal in the sweeping action. The friction lock 61 then holds thebar 50 in place until the treatment is complete.

The neck holding bar 67 is mounted on arms 68 projecting forwardly fromthe post 16 and pivots relative to an outer end the arms 68 on pivotarms 69. Thus the neck holding bar is automatically moved to thedeployed position as shown in front of the squeeze bar 26 as the headgate door 23 is moved to the closed position by a link 70 extending fromthe arm 69 to the gate 23 at a coupling 71 on the torsion bar 34.

In this way the neck holding bar 67 is fixed in the deployed positionand the neck sweep bar 50 is movable to selected adjustable positionsadjacent the neck holding bar depending on the size of the neck of theanimal.

The neck holding bar 67 is bowed from top to bottom so that the animalis fairly free to raise and lower its head when engaged. However thenotch 51 is used to engage the other side of the neck and to morespecifically locate the height of the head and neck when engaged fortreatment.

The swinging movement in the arc A is under control of the worker whocan apply the necessary pressure and speed to the movement to bring thehead to the required location without injury. The entrapment of the headand neck in this way reduces the tendency of the animal to struggle withdanger to itself and the worker and the equipment.

Turning now to FIGS. 7 and 8 , there is shown the latching arrangement72 which holds the gates 23 and 24 in the closed position and can bereleased to allow the gates to move forwardly to the release position orrearwardly to the set position as required.

Thus each head gate door 23,24 includes an engagement portion in theform of an upstanding post 73 with a front face 74 and a rear face 75standing up beyond the top of the gate for cooperating with the latchingdevice 72 for latching the head gate door in the closed position.

The latching device has a front abutment roller 76 for engaging theforward surface 74 of the post 73 to hold the post and thus the headgate door against movement to the forward open position. The latchingdevice has a rear abutment roller 77 for engaging the rearward surface75 of the post 73 to hold the post and thus the head gate door againstmovement to the rearward open position;

The front abutment roller and the rear abutment roller are each movablein an upward direction generally along the common plane containing thesurfaces of the post to release the surface 74 and 75 to allow movementof the head gate door forwardly or rearwardly.

The fact that each of the abutment rollers 76, 77 can rotate on amounting shaft allows the surface of the roller to roll over thesurfaces 74 or 75 as required to reduce friction and allow easy releaseeven when heavily laden by forces from the animal.

The front abutment member of the latch includes two separate rollers 76each for engaging respective post 73 of the respective head gate doors23 and 24. Similarly the rear abutment member of the latch includes twoseparate rollers 77 each for engaging respective one of the head gatedoors. In this way the forces are further reduced as each roller 76 isfree to rotate independently to release its door from the closedposition.

The front abutment member including the rollers 76 is carried on asupport plate 79 carrying the shaft 78. The plate 79 is carried on alower end 81 of a pin 80 which is biased downwardly into a latchedposition by a spring 82. The pin 80 passes through a hole in a supportplate 83 attached to the top rail 12 of the fixed frame of the chute 10.A lift roller 84 is carried on a shaft 85 attached to the plate 79 ofthe front abutment. This roller engages the post 73 of the door as itmoves rearwardly from an open position toward the closed position. Thusthe lift roller 84 lifts the abutment roller 76 to allow the post 73 tomove under the roller 76 into position causing compression of the spring82 as the plate 79 moves upwardly. Once the post passes the roller 76,the roller drops down into engagement position latching the post 73against forward movement. As the roller 77 is already in place, the postand thus the door is latched.

The rear abutment including the roller 77 is exactly symmetrical so thatfurther explanation is not required.

The rollers 76 and 77 are lifted when required by a rotating shaft 86which is rotated about its axis by a handle 87 on either side of thechute 10. Rotation of the shaft 86 acts to tilt an operating plate 88 toone side of the other. The plate 88 engages an upper head 89 of the pin80 acting to lift the pin and therefore the rollers 76. As the plate 88is tilted one way or the other by the handle 87, the operator hascontrol over whether the gate opens either forwardly or rearwardly.

The key feature of the latching system is the provision of the rollers76 and 77 engaging he surfaces of the post which roll to allow the doorto be released even when under heavy pressure from the animal pushingforwardly or pulling rearwardly in an attempt to escape.

In order to better control opening and closing of the gates withoutdanger to the worker or the animal, each of the head gate doors includesa hand grasp handle in the form of a loop 90 welded to the post 73 ofthe rood 24 at a position adjacent the front abutment member projectingforward from the head gate door. This extends from its ends at one post73 across the gap between the posts 73 in front of the gap to provide aconvenient and safe engagement point for the worker to grasp the gatemanually to pull.

In addition, each of the head gate doors at its rail 31 includes aprojecting bar 91, 92 above the respective upstanding squeeze barsextending across from the head gate door toward the other head gate doorso as to prevent the nose of the animal being pinched at the latchingdevice.

Turning back to FIG. 2 , it has previously been described that theupstanding squeeze bar 26, 27 of each head gate door 23, 24 is looselyconnected at an upper end 35 thereof to the upper rail 31 for movementrelative to the upper rail and at a lower end 36 thereof to the lowerrail 32 for movement relative to the lower rail. Further there isprovided an upstanding torsion bar 34 rigidly connected at an upper endto the upper rail 31 and rigidly connected at a lower end to the lowerrail 32 with the upstanding torsion bar 34 being located between theupstanding squeeze bar 26 and the hinge support member 16. In this way,the upstanding torsion bar is arranged so as to twist when forces areapplied to the upstanding squeeze bars 76 and 77 from impact with theanimal where the forces are communicated to the latching arrangement 72located at the upper ends while the bottom ends of the posts 26 and 27pivot about the pivot axis. The torsion bar is welded to the upper andlower rails but can twist and flex so that the bottom rails 32 can pivotforwardly by a distance as much as 4 inches while the upper rail remainsfixed with this amount of movement providing significant spring actionto reduce the loading on the animal as it impacts the bars 26 and 27.

Since various modifications can be made in my invention as herein abovedescribed, and many apparently widely different embodiments of same madewithin the spirit and scope of the claims without department from suchspirit and scope, it is intended that all matter contained in theaccompanying specification shall be interpreted as illustrative only andnot in a limiting sense

The invention claimed is:
 1. An animal confinement apparatus comprising:a generally channel shaped frame structure having a head end forreceiving a head of an animal to be confined, two sides each forextending along a respective side of the animal to be confined, a tailend remote from the head end; a head gate assembly at the head endoperable to move from an open position to a closed position in which theneck of the animal is grasped for confinement thereof; the head gateassembly comprising: a support frame mounted on the frame structure atthe head end; a pair of head gate doors; each head gate door having arespective upstanding squeeze bar for cooperating with a respectiveupstanding squeeze bar of the other of the doors to trap the neck of theanimal therebetween; each head gate door being mounted on a hingesupport member carried on the support frame for pivotal movement of thedoor and its respective upstanding squeeze bar about a respective pivotaxis generally parallel to the respective upstanding squeeze bar andspaced outwardly toward a respective side of the support frame; eachhead gate door comprising an upper rail and a lower rail each connectedto the hinge support member for pivotal movement about the pivot axis;the head gate doors being movable from a closed position in which therespective upstanding squeeze bars lie in a common plane including thepivot axes to a rearward open position in which the respectiveupstanding squeeze bars are positioned on a side of the common planefacing the tail end to allow the head of the animal to enter and to aforward open position in which the respective upstanding squeeze barsare positioned on a side of the common plane opposite the tail end toallow the animal to depart; each head gate door including an engagementportion cooperating with a latching device for latching the head gatedoor in the closed position; the latching device having a front abutmentmember for engaging a forward surface of the engagement portion to holdthe engagement portion and thus the head gate door against movement tothe forward open position and a rear abutment member for engaging arearward surface of the engagement portion to hold the engagementportion and thus the head gate door against movement to the rearwardopen position; the front abutment member being movable in a directiongenerally along the common plane to release the forward surface to allowmovement of the head gate door to the forward open position; the rearabutment member being movable in a direction generally along the commonplane to release the rearward surface to allow movement of the head gatedoor to the rearward open position; the front abutment member comprisinga roller which rotates to roll over the forward surface; the rearabutment member comprising a roller which rotates to roll over therearward surface.
 2. The apparatus according to claim 1 wherein thefront abutment member includes two separate rollers each for engagingrespective one of the head gate doors the rear abutment member includestwo separate rollers each for engaging respective one of the head gatedoors.
 3. The apparatus according to claim 1 wherein the front abutmentmember and the rear abutment member are independently operable.
 4. Theapparatus according to claim 1 wherein the front abutment member and therear abutment member are operable manually.
 5. The apparatus accordingto claim 1 wherein the front abutment member and the rear abutmentmember are located at a top of head gate doors.
 6. The apparatusaccording to claim 1 wherein the engagement portion comprises anupstanding post.
 7. The apparatus according to claim 1 wherein the frontabutment member and the rear abutment member are spring mounted so as tomove to allow entry of the engagement portion therebetween.
 8. Theapparatus according to claim 1 wherein the front abutment member isconnected to a front lift roller for lifting the front abutment memberwhen the head gate door moves toward the closed position and the rearabutment member is connected to a rear lift roller for lifting the rearabutment member when the head gate door moves toward the closedposition.
 9. The apparatus according to claim 1 wherein there isprovided a manually operable member arranged to move the front abutmentmember to a raised position to release the head gate door and arrangedto move the rear abutment member to a raised position to release thehead gate door, the front and rear members being connected to a tiltmechanism to allow to move one or other to the raised position.
 10. Theapparatus according to claim 1 wherein each of the head gate doorsincludes a hand grasp handle adjacent the front abutment memberprojecting forward from the head gate door.
 11. The apparatus accordingto claim 1 wherein each of the head gate doors includes a projecting barabove the respective upstanding squeeze bars extending across from thehead gate door toward the other head gate door so as to prevent a partof the animal being pinched at the latching device.
 12. The apparatusaccording to claim 1 wherein the upstanding squeeze bar of each headgate door is loosely connected at an upper end thereof to the upper railfor movement relative to the upper rail, wherein the upstanding squeezebar of each head gate door is loosely connected at a lower end thereofto the lower rail for movement relative to the lower rail and whereinthere is provided an upstanding torsion bar rigidly connected at anupper end to the upper rail and rigidly connected at a lower end to thelower rail arranged so as to twist when forces are applied to theupstanding squeeze bars from impact with the animal where the forces arecommunicated to the latching arrangement at the upper ends while thebottom ends pivot about the pivot axis.
 13. The apparatus according toclaim 12 wherein the upstanding squeeze bar of each head gate door isloosely connected at the upper end thereof to the upper rail for slidingadjustment movement relative to the upper rail and the upstandingsqueeze bar of each head gate door is loosely connected at a lower endthereof to the lower rail for sliding adjustment movement relative tothe lower rail.
 14. The apparatus according to claim 12 wherein thetorsion bar is welded to the upper and lower rails.
 15. An animalconfinement apparatus comprising: a generally channel shaped framestructure having a head end for receiving a head of an animal to beconfined, two sides each for extending along a respective side of theanimal to be confined, a tail end remote from the head end; a head gateassembly at the head end operable to move from an open position to aclosed position in which the neck of the animal is grasped forconfinement thereof; the head gate assembly comprising: a support framemounted on the frame structure at the head end; a pair of head gatedoors; each head gate door having a respective upstanding squeeze barfor cooperating with a respective upstanding squeeze bar of the other ofthe doors to trap the neck of the animal therebetween; each head gatedoor being mounted on a hinge support member carried on the supportframe for pivotal movement of the door and its respective upstandingsqueeze bar about a respective pivot axis generally parallel to therespective upstanding squeeze bar and spaced outwardly toward arespective side of the support frame; each head gate door comprising anupper rail and a lower rail each connected to the hinge support memberfor pivotal movement about the pivot axis; the head gate doors beingmovable from a closed position in which the respective upstandingsqueeze bars lie in a common plane including the pivot axes to arearward open position in which the respective upstanding squeeze barsare positioned on a side of the common plane facing the tail end toallow the head of the animal to enter and to a forward open position inwhich the respective upstanding squeeze bars are positioned on a side ofthe common plane opposite the tail end to allow the animal to depart;the upstanding squeeze bar of each head gate door being looselyconnected at an upper end thereof to the upper rail for movementrelative to the upper rail; the upstanding squeeze bar of each head gatedoor being loosely connected at a lower end thereof to the lower railfor movement relative to the lower rail; a latching arrangement at a topof the head gate doors which locks the head gate doors in the closedposition while bottom ends of head gate doors at the lower rails arefree to pivot about the pivot axis; and an upstanding torsion barrigidly connected at an upper end to the upper rail and rigidlyconnected at a lower end to the lower rail; the upstanding torsion barbeing located between the upstanding squeeze bar and the hinge supportmember; the upstanding torsion bar being arranged so as to twist whenforces are applied to the upstanding squeeze bars from impact with theanimal where the forces are communicated to the latching arrangement atthe upper ends while the bottom ends pivot about the pivot axis.
 16. Theapparatus according to claim 15 wherein the upstanding squeeze bar ofeach head gate door is loosely connected at the upper end thereof to theupper rail for sliding adjustment movement relative to the upper railand the upstanding squeeze bar of each head gate door is looselyconnected at a lower end thereof to the lower rail for slidingadjustment movement relative to the lower rail.
 17. The apparatusaccording to claim 15 wherein the torsion bar is welded to the upper andlower rails.